I have a weird issue going on. I have a user account and I can login to Gnome normally. From a terminal there I can use su root and switch to root with my root password. However, when I try to login to Gnome as root, the same password does not work.

Be aware that root-gui-login is off for your own protection. Very little GUI software is written with the idea of running with root privs in mind. If you know what you're doing, go for it, but better to log in as yourself. (Even, I think, for people who know what they're doing.)
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mattdmMar 4 '11 at 15:45

It's said that the same change should be applied to "gdm-password", for Fedora 13.
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TshepangMar 4 '11 at 7:55

Yes, it's said on the page I linked to at the bottom: "On Fedora 11 onwards, you also need to edit /etc/pam.d/gdm-password, following the above steps.". I changed the main instructions from /etc/pam.d/gdm to /etc/pam.d/gdm-password based on that.
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MikelMar 4 '11 at 8:49

According to Fedora documentation, the file is called gdm in Fedora 10, and gdm-password in Fedora 11 and above. It sounded like there was no /etc/pam.d/gdm on Fedora 13 based on that.
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MikelMar 4 '11 at 9:26

You must have missed the word also in that page.
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TshepangMar 4 '11 at 10:06